In U.S. Pat. No. 2,840,459, assigned to the same assignee as the present invention, there is disclosed a process and apparatus for the continuous extraction of oils and/or soluble materials from particulate materials comprised of a large vessel forming a vapor-tight enclosure in which there is disposed a rotor including a plurality of cells formed by radially-disposed inner walls extending toward and mounted to peripherally-disposed end walls. A plurality of fluid manifold assemblies are radially-disposed above the cells in a preselect manner to permit the introduction of miscella and solvent stream into the cells, generally to effect a countercurrent extraction utilizing percolation techniques. The bottom of each cell is provided with a hinged-door assembly including associated equipment for opening and closing each cell. Drainage compartments generally underlie the cells for collecting miscella, i.e. a solution of oil and solvent for recycle within the apparatus and eventual withdrawal as described in such aforementioned U.S. patent.
Generally, above one compartment proximate the point of introduction of solids into extractor wherein such solids are contacted with concentrated miscella to form a more concentrated miscella recovered for subsequent separation into extract and solvent, there is provided an inverted V-shaped screen to separate fines from the primary flow of miscella flowing therethrough. The fines together with minor quantities of miscella are caused to flow off the screen into adjacent miscella compartments from which the miscella streams including fines are passed to preselect manifold assemblies for introduction into the cells whereby the fines are essentially filtered into the percolation bed of solids.
In the treatment of shredded sugar cane to extract sugar by the formation of a diffuser juice, the consistency of the shredded cane results in build-up on the inverted V-shaped screen member eventually resulting in blockage and eventual shut-down of extractor operation to permit manual cleaning of such screen member with concomitant reduction in production rates.